I need help..I decided to clean the missus black corsa tonight, first I washed it, then clayed it, then ag super resin polish, I then decided to give it a coat of wax, had no probs waxing my vectra, silver lightning, but when I go to buff the wax off the corsa it seems to leave dark patches that only seem to go away if I rub real hard! Am I putting too much wax on? Not enough? Putting it on with a microfibre is this ok or should I be using a proper applicator? it as if it's discolouring the paintwork slightly unless I put a lot of pressure on when buffing it off(by hand)..any help would be appreciated..sorry no pics because it doesn't show up on a picture..